1. Field of the Invention
The present invention is related to signs, and particularly to signs for displaying characters, which are frequently changed, such as numbers used to indicate prices or the like.
2. Description of Related Art
Signs are frequently used to display prominently the prices being currently charged for products, especially for gasoline, diesel fuel, and the like at service stations, as well as for soda, fresh fruit and vegetables, milk, and other staple food products often sold at roadside stands or advertised and sold in stores. Previously, such signs have frequently utilized separate figures, made, for example, of solid black plastic sheet material cut to the shape of individual digits, with each digit being mounted against a white background which may be internally illuminated to make the sign readable at night. Changes in the prices displayed by such signs require removal of one digit and its replacement by another, different, digit. Therefore, for prices up to and including nine dollars, ninety nine cents ($9.99), twenty-nine separate numeral characters are required in order to be able to display each possible price. Such numeral characters, usually made of rigid plastic sheet material, are subject to being broken, either by being blown off the sign and breaking upon impact with the ground, or as a result of being dropped while numbers are being changed. Once broken, a numeral must be replaced. As a result, spare numerals must be kept on hand, at greater expense and requiring more storage space.
In many circumstances, such as retail sales, it is often desirable to present or display information such as pricing, or even stock or code numbers, relevant to any given item. Thus, for example, in a supermarket or other retailer having high inventory turnover, prices may change from week to week, or possibly even daily. The use of digital figures is commonly known from displays in, for example, CPUs, telephones and digital watches, where the individual figure section contains seven elements which may be activated electronically so as to form a combination showing a figure in the range of 0 to 9. A corresponding display of letters is also possible, but requires a slightly larger number of basic elements to be able to display any letter in the alphabet.
There are several mechanical devices known in the prior art for displaying prices, but they also represent very high and significant capital costs. For example, U.S. Pat. No. 4,115,936 teaches a sign which has self-storing characters that are quickly changeable. However, although the background and the characters may have color contrast and/or illumination, the change is made by moveable shutters--in other words, using moveable and specific mechanical pieces. Obviously, the capital costs of such a device are quite high.
A similar device, having bar segments which may be altered using magnetic material, is shown in U.S. Pat. No. 4,507,888. Yet another device is shown in U.S. Pat. No. 4,539,768. Here again, specific flaps or mechanical means are required to change each segment so as to alter its value.
U.S. Pat. No. 4,858,357 is directed to a reusable card for exhibiting and displaying alphanumeric information, such as a pricing sign for retail use. At least a portion of the face of the card has a background formed thereon in a dark color, and a plurality of multi-segmented alphanumeric presentation display digits. Each of the display digits has at least seven bar segments so arranged as to form the digit "8". Various alphanumeric digits or letters can be formed by changing the color of none or some of the bar segments of each display digit, so as to change its value, using a marker having an ink which is substantially the same color as the color of the background. The card may be reused by wiping the changed display digits with a dampened wiping means which may carry water or a specific solvent, depending on the nature of the ink that has been used in the marker when the display digit was first changed.
Electrically controlled multi-element illuminated signs have become available in recent years, and are convenient to use. Such signs, however, are very expensive to build, operate and maintain. Except for locations atop tall poles along major highways, where prices must be seen at a great distance in order to attract motorists to leave the highway, such signs are too expensive to be practical.
U.S. Pat. No. 5,680,719 describes a display sign having an adjustable "eight" configuration with seven segments. The segments are removably attached to a background member and may be provided with a pressure sensitive adhesive coating. U.S. Pat. No. 4,777,747 discloses a price designating sign using the segmented "eight" configuration in which cover elements may have an adhesive side adhering to a background board 10.
With the exception of the electronic and ink signs, in the above-described signs the numbers are formed by placing various pieces on a background. The ink based sign requires that a specific series of spaces be colored a different color to form a digit. Thus, these signs all are purchased by a user with a background section having no number thereon. These signs come to the user in a number of loose pieces. The sign's background must have the segments "filled-in", either by small pieces or by an ink pen to produce the digit. Thus, the user is required to create each number by placing or coloring a segment in a required position. This requires additional time to assemble and increases the number of loose pieces in a package containing the sign when sent to the user. In addition, when signs contain many loose pieces, there is a chance pieces could be lost. Also, the signs requiring many pieces to form a number are expensive and are not susceptible to a singe use and then disposal.
Accordingly, what is needed is an easily revised display sign which is attractive in appearance, is much less costly than such electrically controllable illuminated signs so as to be disposable, and which does not require the maintenance and storage of a large number of numeral characters which take up a relatively large amount of space while they are not in use.